AnsweredAssumed Answered

AD5292 not changing resistance

Question asked by zi2012 on Apr 15, 2013
Latest reply on Apr 17, 2013 by musach

I have an AD5292 100K ohm pot. The reset pin the the AD5292 is tied to Vlogic. The 20TP memory has never been programmed.

 

I am just trying to get the resistance to change to test my code.  I am using an Arduino to talk to the chip at 4MHz. I have my arduino sending hard coded values to the digipot based on what button I push as a test sequence. My program first sends 0001100000000010 (0x1802) to enable update of the wiper position. Then sends 0000010011111111 to change the wiper to 25% when I push a button.  Well the wiper doesn't change, it stays at 34.8K ohms. Is there something wrong with the SPI data transfers?

 

Scope pictures attached

1 the complete wiper enable

2 close up of the data section

3 the complete 25% command

4 close up of the data section

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